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<title>WEBP - WEBP</title>
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<h1>WEBP - WEBP</h1>

<p>Starting with GDAL 1.9.0, GDAL can read and write WebP images through the WebP library.</p>

<p>WebP is a new image format that provides lossy compression for photographic images.
A WebP file consists of VP8 image data, and a container based on RIFF.</p>

<p>The driver rely on the Open Source WebP library (BSD licenced). The WebP library (at least in its
version 0.1) only offers compression and decompression of whole images, so RAM might be a limitation
when dealing with big images.</p>

<p>The WEBP driver supports 3 bands (RGB) images. It also supports 4 bands (RGBA) starting with GDAL 1.10 and libwebp 0.1.4.</p>

<p>The WEBP driver can be used as the internal format used by the <a href="frmt_rasterlite.html">Rasterlite</a> driver.</p>

<p>Starting with GDAL 1.10, XMP metadata can be extracted from the file, and will be
stored as XML raw content in the xml:XMP metadata domain.</p>

<h2>Creation options</h2>

Various creation options exists, among them :

<ul>
<li><p><b>QUALITY=n</b>: By default the quality flag is set to 75, but this
option can be used to select other values.  Values must be in the
range 1-100.  Low values result in higher compression ratios, but poorer
image quality. <p></li>

<li><p><b>LOSSLESS=True/False</b> (GDAL &gt;= 1.10 and libwebp &gt;= 0.1.4):
By default, lossy compression is used. If set to True,
lossless compression will be used.<p></li>

</ul>

<p>See Also:</p>

<ul>
<li><a href="http://code.google.com/intl/fr/speed/webp/">WebP home page</a></li>
</ul>

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